A gas chromatograph-mass spectrometer data system (GCMSDS) will increase the breadth and the depth of research currently underway in the laboratories of a number of investigators at UCSD and in other institutions in San Diego. The instrument will permit the assessment of a complete spectrum of abnormal metabolites occuring in physiological fluids with inherited metabolic disease. It will permit the development of methods of analysis using isotope dilution methods that will be applicable to prenatal diagnosis as well as the monitoring of experimental therapy. It will also permit the development of a program of investigation using stable isotopic tracers. Many of the participating investigators are members of the Genetic Center at UCSD. Among the disorders under investigation are propionic acidemia, methylmalonic acidemia, glutaric aciduria, combined carboxylase deficiency, and the Lesch-Nyhan syndrome. The instrument will enable detailed studies of the role of amino acids in gout and of prostaglandins in hypertension to be done. It will provide valuable chemical structure information in the organic syntheses of analogs of the antitumor antibiotics mitomycin and the studies of steroids in sexual reproduction of Achyla. The instrument will be used in studies of the biochemical and neurological consequences of vitamin B-12 deficiency in an animal model.